kdb+ and q
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Resolved! How do I add column name as a string to content of data

I have a table contains columns col1, col2. I want to prefix the content of each row in col1 as "col1#". Similarly for col2 as well. Is there anyway i can do with functional update query?   Thanks

KPC by New Contributor II
  • 3 replies
  • 0 kudos

Attributes memory overhead

Out of curiosity, can anyone explain the attributes overhead as explained in the Abridged Q Language Manual? Does anyone know what the 4*u+1 is? for parted and grouped? (I know the 4byte should be probably 8 bytes after 3.0) example overhead `s#2 2 3...

Can't recognise khpun, khp functions...

I'm using the new kdb package which downlaod from Github(https://github.co/KxSystems/kdb), it has the C API interface to convert data into K type. While I write code in Visual Studio and try to compile it, there're error message. Such as: can't recog...

In-place attribute removal

Is there any way to do this? `# looks to always be creating a copy of the original list for `g/`u, whether it's applied on a list reference or value. I wrote a C function to set the list object's u member (x->u) to 0, and from within q called this fu...

Large Scale WindowJoins Questions

Hello Fellow Qbies, I'm attempting to run a wj across a table with a dimension of 1million rows and 30 columns. It works, but it takes too long to run. What are some tips and tricks to dealing with large datasets and windowjoins?

planefan by Contributor
  • 9 replies
  • 1 kudos